The present invention relates generally to the field of surgical instruments and more particularly is directed toward an instrument which is used during ophthalmic surgery to prevent inward collapse of the eye during various surgical procedures.
In typical corneal transplant surgery a section of the eye involving the diseased cornea is removed for replacement by a healthy section. Removal of the diseased section is accomplished by performing a circular incision to a desired depth so that a cylindrical or truncated pyramidal section or plug can be removed. After removing the plug or section a bore-like hole remains for reception of a healthy section or plug which is similarly cut from a donor eye. The circular incision to form the cylindrical or pyramidal section is typically accomplished through the use of corneal trephines or other surgical incision making tools.
During the period between removal of the diseased section and insertion of the healthy section there is the possible danger of the walls of the bore-like opening collapsing inwardly.
Similarly, in surgical procedures to remove cataract lenses it is typical procedure for the surgeon to form a semicircular groove in and about the limbus area of the eye which the surgeon then uses to cut through the eye thus forming a flap to provide access to the anterior chamber of the eye so that the cataract lens may be removed. The formation of the flap which is lifted to provide access to the lens again presents possible danger of collapse of the eye.
In order to overcome the problem of eye collapse during the aforementioned types of ophthalmic surgery, some surgeons have adopted a procedure of suturing a stainless steel ring to the surface of the eye prior to making an incision. Rings of this type (sometimes referred to as a "Flieringa ring") are commercially available, such as for example from the Storz Surgical Instrument Company (catalog number E-4034). The commercially available rings are usually of a diameter such that they will be placed in a position surrounding the cornea so that the surgical procedure takes place radially within the ring.
It is generally accepted that the use of the ring facilitates more accurate wound closure and tends to reduce postoperative astigmatism. At present the only means of securing the ring to the eye is to use a plurality of sutures which pass through the surface of the eye and around the ring. However, before the sutures can be placed, either separate incisions through the conjunctiva must be made, or a 360.degree. conjunctival peritomy is made at the limbus or a combination of separate incisions and peritomy must be made. The conjunctiva can then be dissected back by about 5 millimeters. The ring can then be placed outside the limbus and within the conjunctiva, and sutured to the scleral tissue preferably at 90.degree. intervals between the tendons of the four rectus muscles. This will usually allow sufficient room between the limbus and the ring to perform appropriate surgical procedures.
Because however the use of the ring requires additional delicate surgery and suturing many surgeons fail to take advantage of the benefits afforded by the use of preplacing a ring prior to ophthalmic surgery. Additional incisions to the conjunctiva and placing sutures in the sclera with a high risk of perforation are time consuming and present additional dangers to the patient. Furthermore, the areas for suturing are often difficult to reach with a needle holder. Therefore, many surgeons tend to avoid preplacement of the ring.
It is accordingly the principal object of the present invention to provide a surgical instrument which obviates the foregoing disadvantages in using the Flieringa ring.
A more specific object of the present invention is to provide a ringed type device which simplifies the procedure for attachment to the eye so as to make the use of the ring more acceptable to the surgeon.
Yet a further object of the present invention is to provide a ring having a plurality of securing devices permanently carried by the ring so as to facilitate easy and rapid attachment and detachment of the ring to the eye.
Other objects, features and advantages of the present invention will become more apparent to those skilled in the art from the detailed description of the invention in conjunction with the accompanying drawings to be described more fully hereinafter.